Patent attributes
A bone anchoring device has an anchoring element, a receiving portion, and a pressure element. The anchoring element includes a shank to be anchored in a bone or a vertebra and a head, the head having an exterior surface with a spherical segment-shaped portion. The shank and the head are separate parts. The receiving portion includes a first end, a second end opposite to the first end, a longitudinal axis passing through the two ends, a bore coaxial with the longitudinal axis, and a first region adjacent to the second end for receiving a spherical segment-shaped section of the head. The pressure element exerts pressure on the head to lock the head in the receiving portion. The head has a hollow inner portion to receive a free end portion of the shank and wherein the head and the end portion are formed such that the end portion can be elastically clamped by the head.